Apparatus for the application of liquid corrosion-preventive compound to the inner surface of pipes

ABSTRACT

A device for the application of a liquid corrosion-preventive compound, mainly enamel slip, to the inner surface of pipes in which a pipe installed vertically or at an angle is moved and a compound container connected to the lower end of said pipe relatively to each other vertically to allow the compound to flow from the container into the pipe and back. The device is provided with a float valve installed in the pipe and switching the drive of a hoisting mechanism with the container for lowering as soon as the compound rising inside the pipe acts upon said valve.

United States Patent [191 Podkletnov APPARATUS FOR THE APPLICATION OF LIQUID CORROSION-PREVENTIVE COMPOUND TO THE INNER SURFACE OF PIPES 51 Oct.22, 1974 3.557.749 l/l97l Fill'ilgu ll8/42l Primary Examiner-Louis K. Rimrodt Attorney, Agent, or Firm-Holman & Stern [76] Inventor: Evgeny Nikolaevich Podkletnov,

Smolensky bulvar, 6-8, kv. 144, [57] ABSTRACT M U S S R A device for the agplicatifn of allic} uid cogrosiom preventive compoun main y ename s 1p, tot e inner [22] 1972 surface of pipesin which a pipe installed vertically or [2]] App]. No 233,550 at an angle is moved and a compound container connected to the lower end of said pipe relatively to each other vertically to allow the compound to flow from E 8]. ll8/40lgslcl the container into the pipe and back [58] Field o'r'sii'c'iiffIIffffffIf "1"1' iii i'd''f izi, mo. 10 The device is P i with a fl valve s! in I the pipe and switching the drive of V a hoisting [56] References Cited grechanism wijth the contanezhfor lowering as soon as UNITED STATES PATENTS i vaclzvgompoun rising insi e e pipe acts upon 5211 682,319 9/1901 Clark 118/421 x 2,127,4l3v 8/l938 Leguillon 118/421 X 3 Claims, 1 Drawing Figure I l5 l5 I3 5 5: i=3 2 v {if}; J 522% E 4 7 4 1; T Lzl/l E '5 J l 'l E PAIENIEDWZ Y 3. 42.799

llllmllllmms mmmmummmmlMum-n...

llimimlllllll lHm ,ulm mmimi H N llllllllul lmmllllllmml lllllllin-mnh APPARATUS FOR THE APPLICATION OF LIQUID CORROSION-PREVENTIVE COMPOUND TO THE INNER SURFACE OF PIPES BACKGROUND OF THE INVENTION The present invention relates to a device for the application of liquid corrosion-preventive compound to the inner surface of pipes by filling the pipes with said compound and then draining it.

The corrosion-preventive compound may consist of varnishes, paints, molten plastics, enamel slip and other substances; however the description hereinafter will be made with reference to enamel slip.

PRIOR ART Known in the art is a method of the application of enamel slip to the inner surface of pipes (see, for example, Pat. No. 267297, 1966, Austria). According to this method, enamel slip is drawn into the pipes by a vacuum created therein, and is expelled by compressed air supplied into the pipes. I I

Experence has shown that the slip drawn in by a vacuum cannot fill the pipe accurately to the required level because this process is of the enclosed nature (under vacuum) and cannot be checked; in addition, removal of slip by compressed air results in the blowing off of the applied slip layer. Moreover, compressed air is always polluted with oil (even after the most effective cleaning) finely dispersed in the air, which produces a poor quality of the coating.

OBJECTS AND SUMMARY OF THE INVENTION An object of the invention resides in providing a device for eliminating the above-said disadvantages.

The main object of the invention resides in providing an easily controllable device ensuring a high quality of application of corrosion-preventive compound to the.

inner surface of pipes.

The present application of a layer of liquid corrosionpreventive compound, mainly enamel slip, to the inner surface of the pipe is accomplished by filling the latter with the corrosion-preventive compound and then draining it. In accordance with the invention, the pipe is set at an angle or vertically and its lower end is connected by a pipe to a container with a liquid corrosionpreventive compound after which the pipe and the container are moved vertically with relation to each other to cause the compound to flow from the container into the pipe, after which the pipe and the container are again moved vertically with relation to each other so as to bring the lower end of the pipe higher than the container for draining the compound from said pipe.

Thus, the flow of the compound from the container into the pipe and back is effected on the principle of communicating vessels; hence, by changing the relative heights of the pipe and container, it becomes easy to check the level to which the pipe is filled with liquid compound and to produce a high-quality (nonpolluted) coating.

The present device comprises a container filled with liquid corrosion-preventive compound and a mechanism for delivering said compound from the container into the pipe, and draining it from the pipe. In accordance with the invention, said device consists of a driven hoisting mechanism which moves vertically (up and down) the container connected to the pipe, and a float valve accommodated in the pipe and operably linked with the hoisting mechanism drive being acted upon by the compound rising inside the pipe, the float valve turns on the hoist drive for the lowering movement.

By setting the float valve at a certain height in the pipe, I thus determine the level to which the, liquid compound can rise in the pipe thereby ensuring a possibility of control.

It is practicable that the pipe connecting the container with the pipe being coated be defined a flexible hose or a telescopic pipe.

An advantage of the device lies in the simplicity of its manufacture and operation.

BRIEF DESCRIPTION OF THE DRAWINGS Now the invention will be described in detail by way of example with reference to the accompanying drawing in which the sole FIGURE illustrates a device wherein the container is connected with the pipe by a flexible hose and atelescopic pipe.

DETAILED DESCRIPTION OF THE INVENTION The device comprises a column 1 carrying upper and lower brackets 2 and 3 respectively with grips 4 for holding a pipe5 in an inclined or vertical position. Connected to the lower end of the pipe 5 is a slip container 6 which can be moved up and down with relation to the pipe 5 by any known hoisting mechanism, for example a winch (not shown) whose rope 7 runs over guide rol-' lers 8 and is fastened to the upper part of the container 6.

In one embodiment of the invention, the container 6 is connected to the lower end of the pipe 5 by a flexible hose 9 as shown in the left-hand part of the drawing, while in another embodiment, it is connected by a telescopic pipe 10 as can be seen in the right-hand part of the drawing. In the latter case, a compensating container'lll is an obvious necessity, for receiving the slip when the length of the pipe '10 increases or decreases with the movement of the container 6.

In both cases, the container 6 and the pipe 5 interact as intercommunicating vessels.

To provide for the possibility of controlling the process, the pipe 5 is provided in the interior with, a float valve 12, said valve moving freely with relation to its supporting bracket 13, being acted upon by the enamel slip rising inside the pipe 5.

The valve 12 is linked with the hoise drive (in this case with the winch motor) and, as contacts 14 and 15 close, gives a signal for lowering the container 6 as soon as the pipe 5 is filled with slip to the preset level.

Inasmuch as the valve 12 carries a movable contact 14, electric conductors 17 connected thereto should be given an allowance for length in the form of loops 18.

The invention operates as follows.

The container 6 with enamel slip is moved (at a speed not less than 0.95 m/s) upward by the hoist so that theslip flows into the pipe 5. As the pipe 5 is filled with slip to the preset level, determined by the valve 12, the valve gives a signal for lowering the container 6 which moves below the pipe 5 so that the slip flows from said pipe into said container 6. Part of the slip settles in the form of a layer on the inside surface of the pipe; being dried and baked, this layer produces the enamel coating of the pipe.

Described herein is the simplest embodiment of the invention wherein the container 6 moves with relation to the pipe 5.

It is also possible to move the container 6 and pipe 5 relative to the column 1 to speed up the filling of the pipe with slip i.e., to move the container 6 up and the pipe 5 down when the latter is being filled with slip. For draining the slip, these relative motions are reversed.

Practical employment of the invention has proved its advantages, namely its structural simplicity and ease of operation.

What we claim is:

l. A device for the application of a layer of a liquid corrosion-preventive compound to the inner surface of a pipe comprising: means for holding the pipe in an inclined or vertical position; a container provided with a liquid corrosion-preventive compound; means connecting said container with the lower end of the pipe; a driven hoisting mechanism operably coupled to said container for moving said container up and down with relation to the pipe; and a float valve accommodated inside the pipe and means linking said float valve with the drive of said hoisting mechanism, the arrangement being such that said valve switches the drive for lowering said container as soon as the .valve is acted upon by the liquid compound rising inside the pipe.

2. The device according to claim 1 wherein said means connecting the container with the pipe is defined by a flexible hose.

3. The device according to claim 1 wherein the means connecting the container with the pipe is defined by a telescopic tube. 

1. A device for the application of a layer of a liquid corrosion-preventive compound to the inner surface of a pipe comprising: means for holding the pipE in an inclined or vertical position; a container provided with a liquid corrosion-preventive compound; means connecting said container with the lower end of the pipe; a driven hoisting mechanism operably coupled to said container for moving said container up and down with relation to the pipe; and a float valve accommodated inside the pipe and means linking said float valve with the drive of said hoisting mechanism, the arrangement being such that said valve switches the drive for lowering said container as soon as the valve is acted upon by the liquid compound rising inside the pipe.
 2. The device according to claim 1 wherein said means connecting the container with the pipe is defined by a flexible hose.
 3. The device according to claim 1 wherein the means connecting the container with the pipe is defined by a telescopic tube. 